linux/drivers/acpi/acpica/evgpeinit.c
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   1/******************************************************************************
   2 *
   3 * Module Name: evgpeinit - System GPE initialization and update
   4 *
   5 *****************************************************************************/
   6
   7/*
   8 * Copyright (C) 2000 - 2013, Intel Corp.
   9 * All rights reserved.
  10 *
  11 * Redistribution and use in source and binary forms, with or without
  12 * modification, are permitted provided that the following conditions
  13 * are met:
  14 * 1. Redistributions of source code must retain the above copyright
  15 *    notice, this list of conditions, and the following disclaimer,
  16 *    without modification.
  17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18 *    substantially similar to the "NO WARRANTY" disclaimer below
  19 *    ("Disclaimer") and any redistribution must be conditioned upon
  20 *    including a substantially similar Disclaimer requirement for further
  21 *    binary redistribution.
  22 * 3. Neither the names of the above-listed copyright holders nor the names
  23 *    of any contributors may be used to endorse or promote products derived
  24 *    from this software without specific prior written permission.
  25 *
  26 * Alternatively, this software may be distributed under the terms of the
  27 * GNU General Public License ("GPL") version 2 as published by the Free
  28 * Software Foundation.
  29 *
  30 * NO WARRANTY
  31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41 * POSSIBILITY OF SUCH DAMAGES.
  42 */
  43
  44#include <acpi/acpi.h>
  45#include "accommon.h"
  46#include "acevents.h"
  47#include "acnamesp.h"
  48
  49#define _COMPONENT          ACPI_EVENTS
  50ACPI_MODULE_NAME("evgpeinit")
  51#if (!ACPI_REDUCED_HARDWARE)    /* Entire module */
  52/*
  53 * Note: History of _PRW support in ACPICA
  54 *
  55 * Originally (2000 - 2010), the GPE initialization code performed a walk of
  56 * the entire namespace to execute the _PRW methods and detect all GPEs
  57 * capable of waking the system.
  58 *
  59 * As of 10/2010, the _PRW method execution has been removed since it is
  60 * actually unnecessary. The host OS must in fact execute all _PRW methods
  61 * in order to identify the device/power-resource dependencies. We now put
  62 * the onus on the host OS to identify the wake GPEs as part of this process
  63 * and to inform ACPICA of these GPEs via the acpi_setup_gpe_for_wake interface. This
  64 * not only reduces the complexity of the ACPICA initialization code, but in
  65 * some cases (on systems with very large namespaces) it should reduce the
  66 * kernel boot time as well.
  67 */
  68
  69/*******************************************************************************
  70 *
  71 * FUNCTION:    acpi_ev_gpe_initialize
  72 *
  73 * PARAMETERS:  None
  74 *
  75 * RETURN:      Status
  76 *
  77 * DESCRIPTION: Initialize the GPE data structures and the FADT GPE 0/1 blocks
  78 *
  79 ******************************************************************************/
  80acpi_status acpi_ev_gpe_initialize(void)
  81{
  82        u32 register_count0 = 0;
  83        u32 register_count1 = 0;
  84        u32 gpe_number_max = 0;
  85        acpi_status status;
  86
  87        ACPI_FUNCTION_TRACE(ev_gpe_initialize);
  88
  89        ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
  90                              "Initializing General Purpose Events (GPEs):\n"));
  91
  92        status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
  93        if (ACPI_FAILURE(status)) {
  94                return_ACPI_STATUS(status);
  95        }
  96
  97        /*
  98         * Initialize the GPE Block(s) defined in the FADT
  99         *
 100         * Why the GPE register block lengths are divided by 2:  From the ACPI
 101         * Spec, section "General-Purpose Event Registers", we have:
 102         *
 103         * "Each register block contains two registers of equal length
 104         *  GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
 105         *  GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
 106         *  The length of the GPE1_STS and GPE1_EN registers is equal to
 107         *  half the GPE1_LEN. If a generic register block is not supported
 108         *  then its respective block pointer and block length values in the
 109         *  FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
 110         *  to be the same size."
 111         */
 112
 113        /*
 114         * Determine the maximum GPE number for this machine.
 115         *
 116         * Note: both GPE0 and GPE1 are optional, and either can exist without
 117         * the other.
 118         *
 119         * If EITHER the register length OR the block address are zero, then that
 120         * particular block is not supported.
 121         */
 122        if (acpi_gbl_FADT.gpe0_block_length &&
 123            acpi_gbl_FADT.xgpe0_block.address) {
 124
 125                /* GPE block 0 exists (has both length and address > 0) */
 126
 127                register_count0 = (u16)(acpi_gbl_FADT.gpe0_block_length / 2);
 128
 129                gpe_number_max =
 130                    (register_count0 * ACPI_GPE_REGISTER_WIDTH) - 1;
 131
 132                /* Install GPE Block 0 */
 133
 134                status = acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
 135                                                  &acpi_gbl_FADT.xgpe0_block,
 136                                                  register_count0, 0,
 137                                                  acpi_gbl_FADT.sci_interrupt,
 138                                                  &acpi_gbl_gpe_fadt_blocks[0]);
 139
 140                if (ACPI_FAILURE(status)) {
 141                        ACPI_EXCEPTION((AE_INFO, status,
 142                                        "Could not create GPE Block 0"));
 143                }
 144        }
 145
 146        if (acpi_gbl_FADT.gpe1_block_length &&
 147            acpi_gbl_FADT.xgpe1_block.address) {
 148
 149                /* GPE block 1 exists (has both length and address > 0) */
 150
 151                register_count1 = (u16)(acpi_gbl_FADT.gpe1_block_length / 2);
 152
 153                /* Check for GPE0/GPE1 overlap (if both banks exist) */
 154
 155                if ((register_count0) &&
 156                    (gpe_number_max >= acpi_gbl_FADT.gpe1_base)) {
 157                        ACPI_ERROR((AE_INFO,
 158                                    "GPE0 block (GPE 0 to %u) overlaps the GPE1 block "
 159                                    "(GPE %u to %u) - Ignoring GPE1",
 160                                    gpe_number_max, acpi_gbl_FADT.gpe1_base,
 161                                    acpi_gbl_FADT.gpe1_base +
 162                                    ((register_count1 *
 163                                      ACPI_GPE_REGISTER_WIDTH) - 1)));
 164
 165                        /* Ignore GPE1 block by setting the register count to zero */
 166
 167                        register_count1 = 0;
 168                } else {
 169                        /* Install GPE Block 1 */
 170
 171                        status =
 172                            acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
 173                                                     &acpi_gbl_FADT.xgpe1_block,
 174                                                     register_count1,
 175                                                     acpi_gbl_FADT.gpe1_base,
 176                                                     acpi_gbl_FADT.
 177                                                     sci_interrupt,
 178                                                     &acpi_gbl_gpe_fadt_blocks
 179                                                     [1]);
 180
 181                        if (ACPI_FAILURE(status)) {
 182                                ACPI_EXCEPTION((AE_INFO, status,
 183                                                "Could not create GPE Block 1"));
 184                        }
 185
 186                        /*
 187                         * GPE0 and GPE1 do not have to be contiguous in the GPE number
 188                         * space. However, GPE0 always starts at GPE number zero.
 189                         */
 190                        gpe_number_max = acpi_gbl_FADT.gpe1_base +
 191                            ((register_count1 * ACPI_GPE_REGISTER_WIDTH) - 1);
 192                }
 193        }
 194
 195        /* Exit if there are no GPE registers */
 196
 197        if ((register_count0 + register_count1) == 0) {
 198
 199                /* GPEs are not required by ACPI, this is OK */
 200
 201                ACPI_DEBUG_PRINT((ACPI_DB_INIT,
 202                                  "There are no GPE blocks defined in the FADT\n"));
 203                status = AE_OK;
 204                goto cleanup;
 205        }
 206
 207        /* Check for Max GPE number out-of-range */
 208
 209        if (gpe_number_max > ACPI_GPE_MAX) {
 210                ACPI_ERROR((AE_INFO,
 211                            "Maximum GPE number from FADT is too large: 0x%X",
 212                            gpe_number_max));
 213                status = AE_BAD_VALUE;
 214                goto cleanup;
 215        }
 216
 217      cleanup:
 218        (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 219        return_ACPI_STATUS(AE_OK);
 220}
 221
 222/*******************************************************************************
 223 *
 224 * FUNCTION:    acpi_ev_update_gpes
 225 *
 226 * PARAMETERS:  table_owner_id      - ID of the newly-loaded ACPI table
 227 *
 228 * RETURN:      None
 229 *
 230 * DESCRIPTION: Check for new GPE methods (_Lxx/_Exx) made available as a
 231 *              result of a Load() or load_table() operation. If new GPE
 232 *              methods have been installed, register the new methods.
 233 *
 234 ******************************************************************************/
 235
 236void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
 237{
 238        struct acpi_gpe_xrupt_info *gpe_xrupt_info;
 239        struct acpi_gpe_block_info *gpe_block;
 240        struct acpi_gpe_walk_info walk_info;
 241        acpi_status status = AE_OK;
 242
 243        /*
 244         * Find any _Lxx/_Exx GPE methods that have just been loaded.
 245         *
 246         * Any GPEs that correspond to new _Lxx/_Exx methods are immediately
 247         * enabled.
 248         *
 249         * Examine the namespace underneath each gpe_device within the
 250         * gpe_block lists.
 251         */
 252        status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 253        if (ACPI_FAILURE(status)) {
 254                return;
 255        }
 256
 257        walk_info.count = 0;
 258        walk_info.owner_id = table_owner_id;
 259        walk_info.execute_by_owner_id = TRUE;
 260
 261        /* Walk the interrupt level descriptor list */
 262
 263        gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
 264        while (gpe_xrupt_info) {
 265
 266                /* Walk all Gpe Blocks attached to this interrupt level */
 267
 268                gpe_block = gpe_xrupt_info->gpe_block_list_head;
 269                while (gpe_block) {
 270                        walk_info.gpe_block = gpe_block;
 271                        walk_info.gpe_device = gpe_block->node;
 272
 273                        status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD,
 274                                                        walk_info.gpe_device,
 275                                                        ACPI_UINT32_MAX,
 276                                                        ACPI_NS_WALK_NO_UNLOCK,
 277                                                        acpi_ev_match_gpe_method,
 278                                                        NULL, &walk_info, NULL);
 279                        if (ACPI_FAILURE(status)) {
 280                                ACPI_EXCEPTION((AE_INFO, status,
 281                                                "While decoding _Lxx/_Exx methods"));
 282                        }
 283
 284                        gpe_block = gpe_block->next;
 285                }
 286
 287                gpe_xrupt_info = gpe_xrupt_info->next;
 288        }
 289
 290        if (walk_info.count) {
 291                ACPI_INFO((AE_INFO, "Enabled %u new GPEs", walk_info.count));
 292        }
 293
 294        (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 295        return;
 296}
 297
 298/*******************************************************************************
 299 *
 300 * FUNCTION:    acpi_ev_match_gpe_method
 301 *
 302 * PARAMETERS:  Callback from walk_namespace
 303 *
 304 * RETURN:      Status
 305 *
 306 * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
 307 *              control method under the _GPE portion of the namespace.
 308 *              Extract the name and GPE type from the object, saving this
 309 *              information for quick lookup during GPE dispatch. Allows a
 310 *              per-owner_id evaluation if execute_by_owner_id is TRUE in the
 311 *              walk_info parameter block.
 312 *
 313 *              The name of each GPE control method is of the form:
 314 *              "_Lxx" or "_Exx", where:
 315 *                  L      - means that the GPE is level triggered
 316 *                  E      - means that the GPE is edge triggered
 317 *                  xx     - is the GPE number [in HEX]
 318 *
 319 * If walk_info->execute_by_owner_id is TRUE, we only execute examine GPE methods
 320 * with that owner.
 321 *
 322 ******************************************************************************/
 323
 324acpi_status
 325acpi_ev_match_gpe_method(acpi_handle obj_handle,
 326                         u32 level, void *context, void **return_value)
 327{
 328        struct acpi_namespace_node *method_node =
 329            ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
 330        struct acpi_gpe_walk_info *walk_info =
 331            ACPI_CAST_PTR(struct acpi_gpe_walk_info, context);
 332        struct acpi_gpe_event_info *gpe_event_info;
 333        acpi_status status;
 334        u32 gpe_number;
 335        u8 temp_gpe_number;
 336        char name[ACPI_NAME_SIZE + 1];
 337        u8 type;
 338
 339        ACPI_FUNCTION_TRACE(ev_match_gpe_method);
 340
 341        /* Check if requested owner_id matches this owner_id */
 342
 343        if ((walk_info->execute_by_owner_id) &&
 344            (method_node->owner_id != walk_info->owner_id)) {
 345                return_ACPI_STATUS(AE_OK);
 346        }
 347
 348        /*
 349         * Match and decode the _Lxx and _Exx GPE method names
 350         *
 351         * 1) Extract the method name and null terminate it
 352         */
 353        ACPI_MOVE_32_TO_32(name, &method_node->name.integer);
 354        name[ACPI_NAME_SIZE] = 0;
 355
 356        /* 2) Name must begin with an underscore */
 357
 358        if (name[0] != '_') {
 359                return_ACPI_STATUS(AE_OK);      /* Ignore this method */
 360        }
 361
 362        /*
 363         * 3) Edge/Level determination is based on the 2nd character
 364         *    of the method name
 365         */
 366        switch (name[1]) {
 367        case 'L':
 368
 369                type = ACPI_GPE_LEVEL_TRIGGERED;
 370                break;
 371
 372        case 'E':
 373
 374                type = ACPI_GPE_EDGE_TRIGGERED;
 375                break;
 376
 377        default:
 378
 379                /* Unknown method type, just ignore it */
 380
 381                ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
 382                                  "Ignoring unknown GPE method type: %s "
 383                                  "(name not of form _Lxx or _Exx)", name));
 384                return_ACPI_STATUS(AE_OK);
 385        }
 386
 387        /* 4) The last two characters of the name are the hex GPE Number */
 388
 389        status = acpi_ut_ascii_to_hex_byte(&name[2], &temp_gpe_number);
 390        if (ACPI_FAILURE(status)) {
 391
 392                /* Conversion failed; invalid method, just ignore it */
 393
 394                ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
 395                                  "Could not extract GPE number from name: %s "
 396                                  "(name is not of form _Lxx or _Exx)", name));
 397                return_ACPI_STATUS(AE_OK);
 398        }
 399
 400        /* Ensure that we have a valid GPE number for this GPE block */
 401
 402        gpe_number = (u32)temp_gpe_number;
 403        gpe_event_info =
 404            acpi_ev_low_get_gpe_info(gpe_number, walk_info->gpe_block);
 405        if (!gpe_event_info) {
 406                /*
 407                 * This gpe_number is not valid for this GPE block, just ignore it.
 408                 * However, it may be valid for a different GPE block, since GPE0
 409                 * and GPE1 methods both appear under \_GPE.
 410                 */
 411                return_ACPI_STATUS(AE_OK);
 412        }
 413
 414        if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 415            ACPI_GPE_DISPATCH_HANDLER) {
 416
 417                /* If there is already a handler, ignore this GPE method */
 418
 419                return_ACPI_STATUS(AE_OK);
 420        }
 421
 422        if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 423            ACPI_GPE_DISPATCH_METHOD) {
 424                /*
 425                 * If there is already a method, ignore this method. But check
 426                 * for a type mismatch (if both the _Lxx AND _Exx exist)
 427                 */
 428                if (type != (gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK)) {
 429                        ACPI_ERROR((AE_INFO,
 430                                    "For GPE 0x%.2X, found both _L%2.2X and _E%2.2X methods",
 431                                    gpe_number, gpe_number, gpe_number));
 432                }
 433                return_ACPI_STATUS(AE_OK);
 434        }
 435
 436        /* Disable the GPE in case it's been enabled already. */
 437        (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 438
 439        /*
 440         * Add the GPE information from above to the gpe_event_info block for
 441         * use during dispatch of this GPE.
 442         */
 443        gpe_event_info->flags &= ~(ACPI_GPE_DISPATCH_MASK);
 444        gpe_event_info->flags |= (u8)(type | ACPI_GPE_DISPATCH_METHOD);
 445        gpe_event_info->dispatch.method_node = method_node;
 446
 447        ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
 448                          "Registered GPE method %s as GPE number 0x%.2X\n",
 449                          name, gpe_number));
 450        return_ACPI_STATUS(AE_OK);
 451}
 452
 453#endif                          /* !ACPI_REDUCED_HARDWARE */
 454